Rising more than 600 metres above the surrounding prairies, the
Cypress Hills are a striking geological anomaly on the flat plains.
The hills climb sharply from the north before gradually dropping
back to the plains in the south. Their highest
point (1,466 m) is at "Head-of-the-Mountain."

The Cypress Hills are the highest point in Canada between
Labrador and the Rocky Mountains. Unlike the Rocky Mountains, the
Cypress Hills were not created by the faulting and folding of a
geological uplift. The Cypress Hills are an erosional
plateau formed by millions of years of
sedimentary deposition followed by millions of
years of erosion. Today, the Cypress Hills expose
a unique cross-section of geological history found nowhere else in
western Canada.

The Cypress Hills resemble a giant layer cake composed of many
layers of sedimentary rock. Each layer formed at a different
time under different conditions.

The youngest formations are located higher in the hills.
Sedimentary rocks are made from sediments that are deposited by
water and then compressed and cemented into rock. The grain size of
the rock indicates the environment where the sediments were
deposited. Gravels are deposited only by fast moving streams.
Fine clays are deposited in still water. Most formations are
predominantly a single rock type with thin interbedded layers of
other rock types.

Geological processes slightly elevated the Cypress Hills region
over time. The sedimentary layers remained nearly horizontal but
the area became a drainage divide. Large rivers originating in the
mountains were forced to flow around this divide for millions of
years, which lowered the surrounding land and isolated the Cypress
Hills as a high plateau.

The hard conglomerate cap was resistant to erosion and protected
the softer rock of the underlying formations. This ensured that the
area remained a flat-topped upland. The Cypress Hills had
essentially developed their present form even before the last ice
age.